Process for resolving petroleum emulsions



' Patented Apr. 11, 1939 I PROCESS FOR RESOLVING PETROLEUM EMULSIONSMelvin De Groote, University City, and Leonard L.

Faure, Kirkwood, Mo., assignors to The Tret-O- Lite Company, WebsterGroves, Mo., a corporation of Missouri 7 No Drawing. ApplicationFebruary 28, 1938,

Serial No. 193,062

4 Claims. (Cl. 196-4) This invention relates to the treatment of efiortto indicate whether the solution is molecuemulsions of mineral oil andwater, such as lar or colloidal in nature, The green acids as petroleumemulsions, and has for its object to indicated by their name frequentlygive an aqueprovide a novel process for resolving or breaking oussolution having a dark green or grey-green 5 petroleum emulsions of thewater-in-oil type into appearance. They generally appear as a com- 5their component parts of oil and water or brine. ponent of the aciddraw-off and do not remain The treating agent or demulsifying agentembehind dissolved in the oil fraction which has ployed in the presentprocess is a new composibeen subjected to sulfuric acid treatment. The-tion of A matter consisting of a certain kind of green acids are notsoluble in oil even when subamine salt derived from water-solublepetroleum stantially anhydrous, and certainly are not solul0 sulfonicacid, or acids of the kind hereinafter ble in oil when they contain asmuch as described. Said new material or composition of of water.Similarly, their salts obtained by neumatter may be used either alone,or in admixture tralizing the green acids with a strong solution of withconventional demulsifying agents, such, for caustic soda; causticpotash, or ammonia, are not 15 example, as demulsifying agen'ts of themodified oil soluble. For convenience of classification the 1' fattyacid type, or of the alkylated aromatic ammonium salt will be consideredas an alkali sulfonic acid type. salt.

Petroleum sulfonic acids are produced from a i In contradistinction tothe hydrophile green .wide variety of petroleumdistillates or petroleumacids, there occurs as in the manufacture of fractions and in someinstances they are promedicinal white oil, the oil soluble type or the2g duced from the crude petroleum itself, when mahogany acids. Thesemahogany acids are produced from crude petroleum itself it iscuscharacterized by being soluble in oil, especially tomary to use crudeoil of the naphthene type, when anhydrous, and being soluble in oil evenif crude oil of the paramn type, crude oil of the they containsome'dissolved water. Some of the asphaltic type and mixtures of saidthree differmahogany acids also show limited hydrophiiic 25 ent types ofcrude oil. properties to the extent that either some water The art ofreiining crude petroleum or various can be dissolved in the acids orthey in turn may fractions, using sulfuric acid of various strengthsdissolve to some extent in water. In some inas well as monohydrate andfuming acid, is a stances their salts, such as the sodium, ammowellknown procedure. In such conventional renium, or potassium salt, willdissolve in water to 3( fining procedure, petroleum sulfonic acids havegive a colloidal sol. However, regardless of the been produced asby-products. For instance, in presence of any hydrophilic propertieswhatsoremoving the olefinic components, it has been ever, they alwayshave a characteristic hydrocommon practice to use sulfuric acid so as tophobe property, as indicated by the fact that the polymerize theolefines or convert them into sulsubstantially anhydrous form, forinstance, their 3:

fonic acids which are subsequently removed. alkali salts containing23-12% water, will dissolve Likewise, in the production of white oil orhighly in oil, This clearly distinguishes themfrom the refinedlubricating oils, it has been customary to green acids previouslyreferred to, because the treat with fuming sulfuric acid so as toeliminate green acids in similar form containing the same certainundesirable components. amount of water, for example, will not dissolve4 fonic acids represented the primary objects of Inrecent years, certainmineral oil fractions in oil. The green acids as such are essentiallyhave been treated with sulfuric acid with the hydrophilic andnon-hydrophobic in character. P ry Object of pr Petroleum Sulfonic Theutility of the mahogany acids in various acids, in such Procedure thePetroleum $111 arts has been enhanced by increasing their watersolubility; for instance, converting the mahogany Petroleum sulfonicacid, regardless of whether a'clds into hydroxy alkylamme salts' on theother hand, as far as we are aware, no yaluable gg ggiigggi gg g gz 2 552 2 2: g gig gi product of commerce has resulted from/decreasreactionrather than concomitant by-pro'ducts.

products, tmwit, green-acid or acidshnd mahog ing the water solubilityof the mahogany acids 5 any acid or acids. The green acids are characbythe addition of some on Soluble basic amine terized by beingwater-soluble or dispersible. In such example, tl'lamylafmnee otherwords, they form either true solutions or amylamme Salts of ho a y110168, for e a p sols. For purpose of convenience, they will be arecompletely devoid of any solubility in water herein referred to aswater-soluble without any which the alkali salts may have exhibited andg show, as would be expected, an increased solubility in hydrophobesolvents.

Green acids are hydrophile in character as previously stated, Theirhydrophile character has been increased by neutralization with materialssuch as triethanolamine and the like. Such green acid salts havingenhanced water solubility as compared with the ordinary alkali salts,have found application in certain arts.

We have found that if green acid or acids, that is, the oil-insolubletype, is neutralized with an alicyclic amine so as to produce awater-insoluble product, the resulting material, even though it does notexhibit any marked oil solubility, especially when it contains 5-10% ofwater, still has pronounced value as a demulsifier for oil fieldemulsions, eitherwhen used alone or when used in conjunction with otherknown demulsifying agents, We have also found that sometimes such aminesalt of green acid or acids, will mix in with a hydrophobe material anda hydrophile material so as to produce a homogeneous mixture. Theeffectiveness of the above described material or composition of matteras a demulsifying agent for oil field emulsions, appears to be relatedto $31118 factor other than its solubility characteris- The newcomposition of matter above described, which is employed as thedemulsifying agent in our process, is represented by the alicyclic aminesalt of hydrophilic non-hydrophobic green petroleum acid or acids, asexemplified by the cyclohexylamine salt. The manufacture of said newcomposition of matter involves nothing more or less than neutralizingthe selected petroleum suifonic acid with a suitable amine until neutralto methyl orange indicator, orother suitable indicator., For purpose ofconvenience, we prefer that the selected petroleum sulfonic acidcontains not over 15% of water, It is understood, of course, that theconventional procedure employing dou-' ble decomposition instead ofdirect. neutralization, can be employed new material'or composition ofmatter. For instance, the sodium salt of the selected petroleum sulfonicacid can be dissolved in alcohol and the amine hydrochloride added sothat sodium chloride will precipitate. oil the precipitated sodiumchloride, the alcohol can be evaporated and the amine salt recovered. Ifdesired a mixture of amines instead of a single amine, may be employed.

cyclohexylamine is obtained by the hydrogenation of aniline. Suchcomplete hydrogenation converts an aromatic compound into a hydrogenatedcyclic compound and thus for practical purposes cyclohexylamine may beconsidered as a derivative of cyclohexane- (hexamethylene) Naturallyinstead of using cyclohexylamine, we may use dicyclohexylamine, and ifavailable, tricyclohexylamine might be. employed. Various alkylatedcyclohexylamine derivatives may be obtained by complete hydrogenation of'alkyl derivatives (homologues) of aniline such as toluidine, methylaniline, ethyl aniline, propyl aniline, butyl aniline, amyl aniline,dimethyl aniline, diethyl aniline, ethyl methyl aniline, etc. Completehydrogenation of the aforementioned compound yields the correspondinghydrogenated cyclo compound, such as methyl cyclohexylamine, ethylcyclohexylamine, propyl cyclohexylamine, butyl cyclohexylamine, dimethylcyclohexylamine, diethyl cyclohexylamine, ethyl methyl cyclohexylamine,etc. No distinction is made bein the manufacture of our After filtering-Dicyclohexylamine has one replaceable amine hydrogen and may be reactedwith materials such as ethylene chlorhydrin, glycerol monochlorhydrin,propylene chlorhydrin, etc., so as to produce an hydroxylated alicyclicamine, provided that the corresponding amine" salt of the selectedpetroleum sulfonic acid is water-insoluble. I

It may be well to point out that hydrophile non-hydrophobe petroleumsulfonic acid or acids of the green acid type vary somewhat; forinstance, themolecular weight may vary within the range of 350-500 orthereabouts. Naturally these petroleum sulfonlc acids may carry somepolymerized olefines, free hydrocarbons, or the like, or may even carrya bit of naphthenic acids which represent carboxylated non-sulfonatedpetroleum acids.' As previously stated, these materials are well-knowncommercial products and are available in the open market either in theform of the acid itself or in the form of a salt.

The amine above described may properly be referred to as basic, inasmuchas its basicity is in the neighborhood'of that of ammonia ortriethanolamine. In some instances the basicity may bescmewhat greater,or perhaps slightly less. In order to insure such basicity, it isnecessary that there be no aryl or aromatic radical attached to theamino nitrogen atom. In other words, such materials as phenyldicyclohexylamine, diphenyl cyclohexylamine, and phenyl ethylcyclohexylamine, are not satisfactory, because due to the presence ofthe aromatic phenyl radical or any aryl radical, such as a naphthylradical, attached directly to the amino nitrogen atom, the basicity ofthe amine is reduced to that of aniline or the like, Such amines of lowbasicity do not form stable salts with the petroleum acids of the kinddescribed. The term sulfonic acid used in the claims, is intended tomean and refer to a substance that consists either of a single acid or.a mixture of acids.

Briefly described, our process consists simply in subjecting theemulsion to the action of a de- -mulsifier consisting of the abovedescribed new material or composition ofmatter. Said material is usedeither alone or in admixture with another or with other conventionaldemulsifying agents and its method of use is the same as that generallyemployed in resolving or breaking petroleum emulsions of thewater-in-oil type with a chemical demulsifier. In conformity withconventional practice, the demulsifler may be introduced into the wellin which the emulsion is produced: introduced into a conduit throughwhich the emulsion is flowing; or introduced into a tank in which theemulsion is stored. After treatment the emulsion is allowed to stand ina quiescent state, usually in a settling tank and usually at atemperature varying from atmospheric temperature to about 200 F., so asto permit the water or brine to separate from the oil,

it being preferable to keep the temperature low enough to prevent thevolatilization of valuable constituents of the oil. The amount ofdemulsiher that may be required to break the emulsion may vary from 1part of demulsifier to 500 parts of emulsion up to 1 part of demulsiflerto 20,000 or even 30,000 parts of emulsion. Thenew composition of matterthat is employed as. the demulsifler in our process, constitutes thesubject-matter of our divisional application Serial No. 256,- 728, filedFebruary 16, 1939.

our invention, what we Having thus we p claimt hasnewanddesiretoseourebyLettersPat en 1-. A process for resolving petroleum emulsions s ofthe water-in-oil type. characterized by subject-'instheemulsiontotheactionpi a c awater-insoluble salt of an alicyclicamine or the Mud characterized by the ace of an aryl radios-Fae asuhetituent for an amino 0 hydrogenv atom; said amine salt beingobtained from water-solume non-hydrophobe petroleum sulionic acid omheacid type.

12. A pr so: resolving petroleum emulsions of the water-in-oil type,characterized by sub- 5 jecting the emulsion. to the action of ademulsifler comprising a water-inoohible salt or an all-- cyclic amine;mid amineterized' by the fact that no o hydro atom has been substitutedby any radical other than an m elicyclic radical; and said amine saltbeing obtained from --s'oluble non-hydrophobe petrolemn sulionic acidoithe green acid type.

. iecting' 3. A for resolving petroleum el nulons or the vwater-in-oiltype. charae by subemulsion to the of a demulsialicyclic amine; aminecharacterby the fact that no amino hyen atom has been substituted by anyradical other than a cyclone radical: and said amine salt being obtainedfrom water-soluble non-hydrophobe petroleum sulfuric acid of the greenacid 4. A for resolving petroleum emulsions of the water-in-oil type.charac by subjecting the emulsion to the action of a demuisifler com-awater-insoluble salt derived from cyclohexylamine and water-solublenon-hydrophobe petroleum sulilonic acid or the green acid type.

Eli-I414; VIN DE (3. LEONARD L. FAURE.

. a. water-insoluble of an

